A development of long term evolution (LTE) brings opportunities to both mobile carriers and device original equipment manufacturers (OEMs). According to an increased network capacity and throughput, many new technologies have been emerged. For example, a voice over LTE (VoLTE) technique transmitting voice calls through an LTE network provides salient advantages such as higher efficiency and global roaming. A VoLTE call may provide higher performance metrics than a legacy circuit switching (CS) call and a voice over internet protocol (VoIP) call. However, a reliability of the VoLTE call still lags behind the CS call and the VoIP call. Specifically, a call failure ratio including setup failures and unintended drop situations is almost 5 times higher than legacy calls (e.g., CS call and VoIP call). Therefore, a technique capturing a broader context of VoLTE and learning the correlation pattern between the context and the VoLTE call quality is needed to facilitate more targeted trouble shooting and improve user's calling experience.